Air-propelling cushioning conveyor



Nov. 11, 1969 L. w. SMITH AIR-PROPELLING CUSHIONING CONVEYOR Filed April 15, 1968 ;a\\\v W I 99) INVENTOR LEON W. SMlTHi ATTORNEYS United States Patent 3,477,764 AIR-PROPELLING CUSHIONING CONVEYOR Leon W. Smith, 75 Henderson St.,

Pontiac, Mich. 48053 Continuation-impart of application Ser. No. 593,840, Nov. 14, 1966. This application Apr. 15, 1968, Ser. No. 721,265

Int. Cl. B65g 53/ 06 US. Cl. 302-29 3 Claims ABSTRACT OF THEDISICLOSURE A hollow conveyor bed contains multiple spaced air expansion recesses disposed belowthe level of the top surface of the bed and provided near their rearward edges with upwardly and forwardly inclined air jet nozzle passageways for the discharge of compressed air at high speed in an upward and'forward direction. This action initially produces an expansion in *e'ach recess which dislodges the article to be conveyed and then creates a forwardly-moving cushion of air which simultaneously supports and propels the conveyed article forward while reducingfriction to a minimum. 1 j

This is a continuation-in-part of application Ser. No. 593,840 filed Nov. 14, 1966, now Patent No. 3,411,830, Nov. 19, 1968, for AirCushioning Pneumatic Conveyor, as regards FIGURES 4 and thereof.

I In the drawing:

FIGURE 1 is a top perspective view of an air-propelling cushioning conveyor, accordingto one form of the invention; I

FIGURE 2' is an enlarged top plan view of a the bed and one of the recesses;

FIGURE 3 is a'vertical section taken along the line 33 in FIGURE 2; V s a 7 FIGURE 4 is a vertical longitudinal section through the bed taken along the line 4 -4 in FIGURE 1;

FIGURE 5 is a vertical longitudinal the line 55 in FIGURE 1;. I, 1

FIGURE 6 is an enlarged top plan view ofa modificationofFIGUREZ; 5

FIGURE 7 is a vertical section taken along the line 7-7 in FIGURE 6; a 9

portion of section taken along FIGURE 8 is an enlarged top plan view of a further modification of FIGURE 2; and L 7 FIGURE 9 is a vertical section taken along the line 99 in FIGURE 8 Referring to the drawing in detail, FIGURES 1 to 5 inclusive show an air-propelling cushioning conveyor, generally designated 10, according to one form of the invention as having a conveyor chute 12 including a hollow bed 14, upstanding side walls 16 and a rearward end wall 18 surrounding the bed 14 on three sides. The fourth side or forward end wall 20 of the conveyor chute 12 is lower than the sides 14, 16 and 18 so as to provide a forward outlet end or discharge opening 22. The conveyor chute 12 (FIGURE 4) is composed of lower and upper units 24 and 26 respectively, the lower unit 24 being shaped somewhat like a shallow baking pan and containing the side and end walls 16, 18 and 20, nad has a bottom wall 28 which is drilled and threaded at spaced locations 30 along its periphery to receive threaded fasteners 32 passing through the correspondingly drilled upper unit 26 and also through spacing bars 34 of elastic deformable material, such as natural or synthetic rubber or resilient synthetic plastic. The spacing bars 34 serve to seal the air chamber 36 within the hollow bed 14 against undesired leakage of air.

Near its forward end wall 20 (FIGURE 5), the conveyor chute 12 has its bottom wall 28 provided with an inlet port 38 Which communicates with a threaded inlet fitting 40 welded or otherwise secured as at 42 to the bottom Wall 28. Threaded into the fitting 40 is the upper end of a correspondingly threaded compressed air inlet pipe 44 which leads to an air compressor (not shown) either directly or by way of a compressed air reservoir (also not shown).

The upper unit 26 constitutes the top wall of the hollow bed 14 and at laterally and longitudinally-spaced locations is provided with multiple air-expansion recesses 46 (FIGURES '2 and 3), each disposed below the top surface 48 of the upper unit 26 and each containing an upwardly and forwardly-inclined air jet nozzle port or passageway 50, the lower end of which communicates with the air chamber 36. Theports or holes 50 are located at the rearward side of their respective recesses 46, that is, nearer the rear wall 18 than the forward wall 20 of the conveyor chute 12 and on the rearward side of the center 52 of each recess 46. To simplify the discl sure, only a few of the recesses 46 have been shown in FIG- URE 1, only the centers 52 of the remainder thereof be ing illustrated. In the form of the invention shown in FIGURES 1 to 5 inclusive, the recesses 46 are of approximately conical shape and conveniently made by the correspondingly conical end of a conventional rotary drilling or countersinking tool.

. In 'the modification, generally designated 60, shown in FIGURES 6 and 7, the recesses 62 in the top wall 64 corresponding to the upper unit or top wall 26 of FIG- URE 3 are conveniently formed by an indenting tool of corresponding shape, such as for example a conventional punch mounted in a conventional press, which forms bulges 65 whose convex surfaces 67 project downward into the air chamber 36. The lower unit 24 and the remaining construction is the same as that shown in FIG- URES 1 to 5 inclusive and the air discharge ports 66 similarly located, like the air discharge ports 50, nearer the rearward side of each recess 62 and similarly inclined in an upward and forward direction. As before each recess 66 is located entirely below the top surface 68 .of the top wallv 64 and the ports 66, also as before, communicate with the air chamber 36.

In the further modification, generally designated 70, shown in FIGURES 8 and 9, the top wall 72 .at laterally andlongitudinally-spaced; intervals therein: is provided with upwardly and forwardly inclined air expansion recesses 74, each having bottom walls 76 and an annular side wall 78. Opening into each air expansion recess 74 is an upwardly and forwardly inclined; air jet nozzle passageway 82 in the rearward portion of the side wall 78. The recesses 74 and their upwardly and forwardly inclined bottom walls 76 and variable side walls 78 are conveniently formed by punch-and-die or stamping operations in conventional presses.

In a similar manner, at locations corresponding to the locations of the recesses 74, the bottom walls 76 are engaged by correspondingly inclined upstanding protuberances 84 in a bottom wall 86 of a lower unit 88 (FIG- URE 9). Each protuberance 84 has a downwardly and rearwardly inclined top wall 90 and a variable annular side wall 92. Each side wall 92 and the downwardly facing recesses 94 caused thereby are of such height as to locate the top wall 90 in alignment with and immediately below the correspondingly inclined bottom wall 76 of each corresponding recess 74 in contacting engagement therewith. This construction thus provides air jet nozzle passageways 82, the axes 96 of which are parallel to the upwardly and forwardly inclined bottom wall 76 and coincide with the direction of jet air flow of the compressed air emerging through the nozzle opening 82 3 from the air chamber 98 located between the lower unit 88 and the top wall 72. The lower unit 88 in other respects corresponds in construction to the lower unit 14 of the conveyor chute 12 shown in FIGURES 1 to 5 inclusive and has similar front, rear and side walls (not shown). From FIGURES 2 and 3, 6 and 7, and 8 and 9, it will be seen that each respective air expansion recess 46, 52 or 74 has walls extending continuously therearound, and unbroken except for its respective tiny jet nozzle passageway 50, 66 or 82; also that the cross-sectional area of the top of each said recess is a multiplicity of times the cross-sectional area of each said passageway so as to impart a high speed to the air stream emerging therefrom for propelling the conveyed article.

In the operation of the invention, in any of the three forms shown in FIGURES l to 9 inclusive, let it be assumed that the conveyor chute 12 has been positioned with its closed or rearward end wall 18 adjacent the outlet of the machine or other source from which articles to be conveyed are dropped or otherwise deposited and that the discharge opening 22 is disposed above or adjacent the point of article reception, such as a tote bin, a moving belt conveyor or the like. Due to the manner of operation of the conveyor 10, 60 or 70, it does not require tilting in order to overcome the frictional drive of gravity present in ordinary conventional chutes and, provided the air jets emerging from the air jet nozzle passageways or holes 50, 66 or 82 are powerful enough may even permit the discharge opening 22 to lie even with or above the rearward article intake location adjacent the rearward end wall 18.

As compressed air is supplied to the air chamber 36 or 98 through the air supply pipe 44, coupling 40 and air inlet port 38, it emerges at high velocity through the multiple inclined air jet nozzle passageways 50 in the rearward portions of the recesses 46, 62 or 74 in the direction of the axis of each hole 50, 66 or 82 as indicated by the arrow 96 in FIGURE 9. Any air which spreads downward after emerging from the air jet nozzle passageways 50, 66 or 82 is immediately deflected upward and forwardly by the upwardly and forwardly inclined bottom wall or surface 46, 62 or 74 of the respective recesses. The compressed air, after emerging from the multiple air jet nozzle passageways 50, 66 or 82 forms a moving beltlike cushion of compressed air which initially expands within its respective recess 46, 62 or 74 until it develops suflicient force to dislodge and lift the conveyed articles off the top wall 26, 64 or 72 of the conveyor 10, 60 or 70, whereupon the high speed of the jet air streams emerging from their tiny passageways 50, 66 or 82 then propels the articles forwardly toward and through the discharge opening 22 onto or into a chosen place of article disposal.

Since the article being conveyed is lifted away from the top wall 26, 64 or 72 out of contact therewith, it has no frictional engagement therewith, and the only frictional effect present is that between the faster moving air cushion and the article being conveyed. This, however, is of neglibible amount in contrast to the friction existing between an article and the bottom wall of a gravity chute in direct frictional contact therewith.

I claim:

1. An air-propelling cushioning conveyor, comprising a chute having a rearward inlet end and a forward outlet end and a hollow bed having a top surface extending from said inlet end to said outlet end,

said bed having multiple air expansion recesses disposed below the level of said top surface and each recess having an air jet nozzle passageway therein opening therein near the rearward end thereof and inclined upward and forward toward said outlet end of said chute,

each said recess having a wall extending continuously therearound and unbroken except for its respective air jet nozzle passageway,

each said wall having a portion thereof inclined upward and forward away from its respective jet nozzle passageway in the direction of the jet discharge from said passageway toward said outlet end of said chute, the cross-sectional area of the top of each said recess being a multiplicity of times the crosssectional area of each respective air jet nozzle passageway, an air chamber communicating with said nozzle passageways, and means for supplying compressed air to said air chamber.

2. An air-propelling cushioning conveyor, according to claim 1, wherein said recesses are of approximately conical configuration.

3. An air-propelling cushioning conveyor, according to claim 1, wherein said recesses comprise the concave upper surfaces of indentations having convex lower surfaces project downward into said air chamber.

References Cited UNITED STATES PATENTS 3,099,493 7/ 1963 De Hart et a1 302-29 1,515,965 11/1924 Pardee 302-31 3,181,916 5/1965 Epstein 302--29 3,232,673 2/1966 Selig et al 302--29 FOREIGN PATENTS 797,371 7/ 1958 Great Britain. 1,056,003 10/ 1953 France.

ANDRES H. NIELSEN, Primary Examiner 

